Process for pouring liquid melts from metallurgical vessels

ABSTRACT

A process and apparatus for pouring a liquid melt from a metallurgical vessel such as a ladle wherein the pouring-out opening is provided with a solidification-preventing, loose filler, before the vessel is filled with the liquid melt. The pouring-in opening of the container prior to pouring which receives the liquid melt is covered with a protective screen inclined in relation to the axis of the pouring jet. The screen consists of a material that cannot be inflamed by the filler but is inflammable by the melt. The protective screen between the pouring-out opening of the vessel and the pouring-in opening of the container to receive the liquid melt may be paper, cardboard or a readily inflammable synthetic resin. The screen may have a thickness of about 1 - 2 mm and a smooth surface on the side which faces the outflowing melt. The screen may be a conically shaped protective screen or a roof-shaped protective screen.

United States Patent [191 Schnurrenberger 1 51 May 1, 1973 [75] Inventor: Emil Schnurrenberger, Steinhausen.

Zurich, Switzerland [73] Assignee: Interstop AG, Zug, Switzerland 22 Filed: Dec. 30, 1971 [21] Appl. N0.: 214,165

[30] 7 Foreign Application Priority Data Jan. 8, 1971 Germany ..P 2] ()0 632.6

52 US. Cl ..164/134, 249/205 51] Int. Cl. ..B22d 7/12 58 Field of Search ..l64/l34, 337, 412; 249/205, 206

[56] References Cited 7 UNITED STATES PATENTS 947,835 2/1910 Meissner ..l64/l34 X FOREIGN PATENTS OR APPLICATIONS 1,132,297 6/1962 Germany .249/206 Primary Examiner-Robert D. Baldwin Attorney-E. F. Wenderoth et al.

57 ABSTRACT A process and apparatus for pouring a liquid melt from a metallurgical vessel such as a ladle wherein the pouring-out opening is provided with a solidification preventing, loose filler, before the vessel is filled with the liquid melt. The pouring-in opening of the container prior to pouring which receives the liquid melt is covered with a protective screen inclined in relation to the axis of the pouring jet. The screen consists of a material that cannot be inflamed by the filler but is inflammable by the melt. The protective screen between the pouring-out opening of the vessel and the pouringin Opening of the container to receive the liquid melt may be paper, cardboard or areadily inflammable synthetic resin. The screen may have a thickness of about 1 2 mm and a smooth surface on the side which faces the outflowing melt. The screen may be a conically shaped protective screen or a roof-shaped protective screen.

7 Claims, 5 Drawing Figures PROCESS FOR POURING LIQUID MELTS FROM METALLURGICAL VESSELS The invention relates to a process for pouring liquid melts from metallurgical vessels such as particularly ladles, wherein a solidification-preventing, loose filler is introduced into the discharge opening of the vessels prior to the filling of the vessels with the liquid melt, which filler is to prevent a solidification of the melt in the relatively narrow through-flow channel prior to the start of pouring casting and to secure an uninterrupted pouring-out of the melt.

Especially in the case of ladles equipped with bottom closure devices, it is well known to fill the through-flow opening of the refractory pouring-out block or nozzle arranged in the refractory bottom block of the ladle, with sand before the ladle is filled with liquid melt so that prior to the start of the pouring, the melt does not solidify in the relatively narrow through-flow channel of the pouring-out block or on the shutoff member such as a slide plate of a slide closure arranged below the discharge opening. The sand which is introduced in advance prevents the contact of the melt, introduced into the ladle, with the freezing-promoting zones of the refractory ceramic closure parts, that are relatively colder in relation to the bottom brickwork of the ladle which is subjected to the direct action of the melt. This process has the disadvantage that, during the pouring, the sand introduced in advance reaches the casting mold and contaminates the casting. In order "to avoid such a contamination, it is also possible to pour out initially over a scrap iron mold, then to close the discharge opening and, subsequently, to start the pouring procedure proper. However, especially in the case of high-alloy steels, valuable melt material is lost in this connection, so that one does not like to apply this procedure for reasons of its wastefulness.

Indeed, in the metal casting procedures used for hollow castings of complex shapes in sand molds, it has been already attempted to keep the impurities, such as slag and sand, from penetrating into the casting mold by covering the funnels or the sprue above the casting mold with an iron, steel or metal plate prior to pouring. In this manner, the metal poured into the pig pouring tray or casting basin is not permitted to reach the mold directly; rather, the impurities can be skimmed off or ladled out first so that, after the cover plate is melted through, the melt in pure state flows into the mold. However, this known process is not suitable for chill casting or group casting such as bottom pouring of multiple molds because the procedure does not involve the use of a pig pouring-in tray which can serve as a reservoir until the impurities are skimmed off or ladled out. Besides, the skimming off is time-consuming. and the time delay caused by the required melting of the cover plate is not desirable for the casting procedure proper, quite apart from the fact that this method is not very reliable for keeping away the impurities to which, ultimately, belongs also the-melted cover plate, especially in the case of high-alloy refined steels.

An object of the invention is to avoid the known difficulties and disadvantages and to produce a process associated with an apparatus for pouring liquid melts, which process and apparatus should prevent in a reliable manner the entry of sand (introduced in the pouring-out spout of the pouring vessel before the vessel is filled, for the purpose of preventing the freezing) into The invention solves the problem in such a manner that, prior to pouring, the pouring-in opening of the container which receives the liquid'melt is covered with a protective screen inclined in relation to the axis of the pouring jet and consisting of a material that cannot be inflamed by the tiller but is inflammable by the melt, preferably paper. This protective screen may advantageously consist of a paper material having a thickness of l 2 mm and a smooth surface on the side facing the outflowing rnelt. In this manner, 'there is attained a considerable advantage with a low expenditure: the solidification-preventing filler, e.g., sand, which is discharged first during the pouring from the spout of the pouring container, slides over the inclined surface of the protective screen laterally beyond the edge of the casting mold or chill and the following liquid melt passes into the mold or chill free of impurities while the protective screen is burned.

A further object is to provide the protective screen in the shape of a cone or a roof.

With the above and other objects in view which will become apparent from the detailed description below, some preferred embodiments of the invention are shown in the drawings, in which:

FIG. 1 is a perspective view of a protective screen in the shape of a hollow cone;

. FIG. 2 is a similar view of a roof-shaped embodiment of such a screen;

FIGS. 3 5 show cross-sectional views of examples of application of the process of the invention employing a protective screen.

FIG. 3 shows a hollow-cone protective screen of paper 1 which, in the case of top casting, is placed as it were a hat on a chill 2 in front of the spout 3 designating the spout of a casting ladle, which is not illustrated, and it can be seen that, during pouring, sand 4 which is discharged first from the spout slides over the protective screen and along the sides of the chill. The

procedure is carried out in the same manner in FIG. 4

which illustrates the bottom casting procedure. The protective screen 1 is placed on the funnel of a funnel pipe 5. I

In FIG. 5, which represents a continuous casting operation the protective screenl is placed over a pouring-in opening 6 of a tundish 7.

The protective screen may also be suspended from the spout as by means of a wire. Besides, it may consist of cardboard or a readily inflammable synthetic resin.

I claim:

I. A process for pouring a liquid melt froma metallurgical vessel to a container comprising providing a solidification-preventing loose filler in the pouring-out opening of said vessel before said vessel is filled with the liquid melt, covering the pouring-in opening of the container prior to pouring with a protective screen inclined in relation to the axis of the pouring jet and consisting of a material that cannot be inflamedby said filler but is inflammable by said melt, and discharging said filler from saidopening whereby the filler material slides over the inclined surface of said screen followed by the liquid melt which inflames said screen and passes into said container.

2. Theprocess of claim 1 wherein said vessel is a ladle and said containeris a mold.

3. The process of claim 1 wherein said vessel is a shaped. ladle and Said coTltamerisamndlsh- 7. The process of claim 1 wherein said screen is 4. The process of claim 1 wherein said vessel is a ladle and said container is a funnel pipe.

5. The process of claim 1 wherein said screen is coni- 5 cally shaped.

6. The process of claim 1 wherein said screen is roofformed of paper having a thickness of about 1-2 mm and a smooth surface on the side which faces the overflowing melt. 

1. A process for pouring a liquid melt from a metallurgical vessel to a container comprising providing a solidificationpreventing loose filler in the pouring-out opening of said vessel before said vessel is filled with the liquid melt, covering the pouring-in opening of the container prior to pouring with a protective screen inclined in relation to the axis of the pouring jet and consisting of a material that cannot be inflamed by said filler but is inflammable by said melt, and discharging said filler from said opening whereby the filler material slides over the inclined surface of said screen followed bY the liquid melt which inflames said screen and passes into said container.
 2. The process of claim 1 wherein said vessel is a ladle and said container is a mold.
 3. The process of claim 1 wherein said vessel is a ladle and said container is a tundish.
 4. The process of claim 1 wherein said vessel is a ladle and said container is a funnel pipe.
 5. The process of claim 1 wherein said screen is conically shaped.
 6. The process of claim 1 wherein said screen is roof-shaped.
 7. The process of claim 1 wherein said screen is formed of paper having a thickness of about 1-2 mm and a smooth surface on the side which faces the overflowing melt. 